If you go down to the Token subforum on this site, you will see an explanation from me on another token series. Yours is much the same, but deals with Upper Canada rather than Montreal Tokens. Tokens in your series were made for 1850, 1852, and 1854. They are sometimes referred to as St Georges tokens because it has a design of St Georges slaying the dragon on the Obverse. All Canadian tokens, from the early 1800's until Canadian decimal coinage was started in 1858 & 9, were struck by banks and merchants because there was nothing else. There was a huge shortage and only foreign coinage of different denominations and countries existed. Bank tokens were struck in the same sizes and denominations as British coinage .. pennies and half pennies.

The Bank of Upper Canada tokens are quite common, although there are a few scarcer varieties. You can normally find F and below tokens of any denomination in dealer junk bins or the buck pile. They are, in my opinion, very well struck and intersting coins. Go to any library on either side of the border and read a copy of Charlton's Canadian Colonial Tokens .. it will probably be in the reference section so you can't check it out. If the library doesn't carry a copy, it can be special ordered as reference material and borrowed from another library that does.. no cost.